Dental instrument.



R. H. GALLAGHER & R. E. DUTGHER.

DENTAL INSTRUMENT. APPLIoATIoNrILHnJULYa,190s.

9 1 6,856 Patented Mar. 30, 1909.

3. @ya L '1.5. f7 ^/7 7/////////////////y///////7/////////I/ll ATTORNEYS' W/TNEss/Es ,y

Tun nanRls Plums co4, wmaow, n4 c.

lllallltlhll) tisfillfts ROY H. GALLAGHER AND RAYMOND E. DUTCHER, OF PLAINVIEW, NEBRASKA.

DENTAL NSTRUMENT.

Specification of Letters Patent.

Application filed July 3, 15308.

Patented March 80, 19G9.

Serial No. 441,816.

To all' ywlw/mf it' may con/cern.'

Re it. known that ive, Roi' H. GALLaGHni-z as l .mn Dr'rcnniz, citizens of the United `htates, and residents of Plainview, iu the county ot Fierce and State of Neira, have raade certain new and useful i Movements in Dental instruments, of which the following is a specilication.

@ur invention relates to dental instru- 13s, and is an improvement in those ap- .nees used toi. the purpose oit' extract- A roots et' teeth which are broken or def ved oit too iai' to grasp with forceps, oo trail. to stand the pressure of creeps without crushing and breaking ofi', even it vthey are long enough to be engaged by the instrument. Various devices have been proposed tor accomplishing this purpose, and seine of these devices are in use.

@ne in which iQ coinnionly niet With consists o* long round shank having1 a tap on re ced end portion, and a nuinber of screw cada above the tap. This instrument is desigi'ied to be inserted in a canal oit the tooth and to be rotated after the inanner ot the ordinary cork screw. rlhe terniinal tap cuts its Way through the material of the tooth and the screw threads enter the grooves thus prepared to give a iirin hold on the tooth. @ne disadvantage of the use t this instruni ent is that the screw naturally has a vfedging action and tends to split the root, which is thereby rendered still more diiicult to extract. `liiloreover, the operation of cutting into the tooth. by this instrument may occasion pain to the patient, especially it the tooth is sore.

Our invention has for its object the provision of a device for extracting the roots ot teeth, in which a iirni hold niay be secured upon the root Without danger ot splitting the latter.

A Jfurther object is to provide a device Figure l is a view of a double-barbed instrunient in its norinal condition With the barbs extended. Fig. 2 1s a view of a doublel i l i l l r l i l l l barbed instrument with the barbs closed. .Fi 3 is a vieiv of a diliperenttorni shotvinga singlebarbed instrument With its barb in operative position. Fig. e; is ay view of a singlebarbed instrument showing the barb closed. Fig. 5 is a view of anothertorin showing a double-barbed instruinent, the barbs in this case being pivoted at diii'erent points. Fig. 6 is a detail vieiv showing the relation or" the barbs in Fig. 5. Fig. 7 is a view showing a diilerent arrangement of the two barbs shown in Figs. l and 2. Fig. 8 is a vien ot' a right angled handle for use with our invention. Fig. 9 is a side View of the instrument showing the end slot and the manner in which the barbs are secured.

Referring now to the drawing, l denotes a shank or stein which niay terminate at one end in a loop or ring 2, or in any other convenient forni. rlhe opposite end of the shank is provided with a threaded socket 9, arranged to receive the scren7 fr et an exten-- sion rlhe nieinber 5 consists preferably of a cylindrical piece oit steel provided with a slot in one end thereof, and having at its outer end a pivot pin 7, Which is secured between the tivo branches of the slotted ineinber 5. Pivoted upon the pin 7 are tivo barbs S and 9. These barbs are normally acted upon by the springs l0 and l1, which tends to keep there swungoutivardly. lt will be noticed that these barbs are or" a peculiar shape, which is clearly shown in Figs. G and l Each ot these barbs is provided With a serrated edge and the barbs are made of the best steel available for purposes of this kind. lt will be observed that the barbs are convex on one side and concave on the other. The pivot pin T is also made ot' hardened steel and of sutlicient size to bear a considerable strain.

In Fig. 2 We have shown the barbs as being closed. le inay also niake the instrunient with a single barb, as shown in Figs. 3 and t.

In Fig. 5 We have shown a different torni, in which the barbs on either side of the instrument are not pivoted on a connnon pivot but have separate pivots 13 and 14, one above the other. This provides an instrui 'nient which is especially adapted for use in extracting teeth with long roots. rlhe inanner in which the barbs are kept spread apart is clearly shown in Fig. 6. l'n this iigure the loverniost barb 8 has upon it a projection or stud 12, which, as long as the with a threaded slot in its laterally projecti end is inserted into the canal of the tooth,

barb 8 is in a closed position, does not bear l upon the barb 9, but which is designed to operate the barb 9 so as to move the latter away from its normal position, when the barb 8 is moved by the spring 1 0.

in order to reduce the length of the pivot pin and consequently the six/.e of the instrument, we may arrange the two barbs shown in Fig. 1 in the manner illustrated in Fig. 7. -1n this ligure each of the barbs S and 9 has a cut away portion 15 and the barbs are provided with openings 16, which are arranged to register, and through which the pivot pin is adapted to pass. The cut away portions 15 are placed together, so that when the two barbs are assembled, they require a slot of only the same size as either one of them and the barbs themselves lie in the same common plane.

ln Fig. 8 we have shown a right angled handle attachment 17, which is provided ing stem i8, arranged to receive the threaded portion 19 bearing the barb at its lower extremity.

ln the use of our instrument the barbed the barbs during the insertion yielding and permitting the instrument to enter tar enough to get a good grip on the root. T he serrated points of the barbs are maintained against the walls ci the canal by means oi' the springs and when noiY pressure is exerted in the opposite direction by a pull, the sharp points of the barb out through the soft or decayed part of the tooth into harder material, spreading out as the torce increases, and each moment getting a iii-mer grip upon the root, by which means the root may be extracted. lt will be seen at once that this operation comparatively simple and that there is no preliminary fastening ot' the instrument to the tooth preparatory to extracting it. Moreover, there is not the danger of splitting the tooth that there is in employing a screw having a wedging action all around as has been described.

In the use of our improved root extractor, if one of the barbs is broken it can be easily replaced by another one at small cost, while in the case ot the tap and screw extractor, if the small end is broken olf, the instrument is rendered valueless. Moreover, the barbs can be sharpened without removing them from the shank if they should become dull.

Ne are aware that other constructions than those shown herein, based upon the same general idea, may be made, but we consider and desire to claim as our own all such modifications as fairly fall within the spirit and scope of the invention.

Manifestly, when so desired, the shank or handle and the barb holding extension may be integral instead of connected by threaded joint as shown in Figs. 1 to 5. It will also be understood that one, two or more barbs may be used on each instrument; that the barbs may be made with or without the cut away portions and that the instruments may be made in different sizes to suit the work i'or which they are designed.

The instrument, as shown and described, possesses many advantages in addition to those before enumerated. Thus it will not slip out or become clogged in use and is capable ot' efiicient use when the instruments ordinarily employed tor the purpose are ineffective.

Vile claiml l. A tooth root extractor comprising an operating handle, one or more spring actuated curved barbs pivoted in the end of said handle with their outer points normally distended, the concave edges of said barbs being turned toward the operating end of the device, thereby maintaining the points in a position practically at right angles to the side walls of the tooth.

2. ln a dental instrument, a device substantially as described, comprising a handle, and upper and lower barbs pivoted thereto, one of said barbs having a stud or projection to engage and operate the other barb.

3. ln adental instrument, a handle provided with a slot, upper andY lower barbs pivoted thereto and arranged to enter said slot and having their pivotal points lying in the central axis of the handle, one of said barbs having a stud or projection to enga-ge and operate the other barb, and a spring for operating the first named barb.

ROY H. GALLAGHER. RAYMOND E. DUTCHER. lllitnesses Gr. F. DURLAND, H. L. BUcxINGi-IAM. 

